A working checklist of accepted taxa worldwide is vital in achieving the goal of developing an online flora of all known plants by 2020 as part of the Global Strategy for Plant Conservation. We here present the first-ever worldwide checklist for liverworts (Marchantiophyta) and hornworts (Anthocerotophyta) that includes 7486 species in 398 genera representing 92 families from the two phyla. The checklist has far reaching implications and applications, including providing a valuable tool for taxonomists and systematists, analyzing phytogeographic and diversity patterns, aiding in the assessment of floristic and taxonomic knowledge, and identifying geographical gaps in our understanding of the global liverwort and hornwort flora. The checklist is derived from a working data set centralizing nomenclature, taxonomy and geography on a global scale. Prior to this effort a lack of centralization has been a major impediment for the study and analysis of species richness, conservation and systematic research at both regional and global scales. The success of this checklist, initiated in 2008, has been underpinned by its community approach involving taxonomic specialists working towards a consensus on taxonomy, nomenclature and distribution.

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Urbanisation introduces deep changes in habitats, eventually creating new urban ecosystems where ecological functions are driven by human activities. Th e higher frequency of some phenotypes in urban vs rural/wild areas has led to the assumption that directional selection in urban habitats occurs, which may thereby favour some behavioural and physiological traits in urban animal populations compared to rural ones. However, empirical evidence of directional selection on phenotypic traits in urban areas remains scarce. In this study we tested whether eumelanin-based colouration could be linked to survival in two urban populations of the feral pigeon Columba livia . A number of studies in diff erent cities pointed out a higher frequency of darker individuals in more urbanised areas compared to rural ones. To investigate whether directional selection through survival on this highly heritable trait could explain such patterns, we conducted mark -recapture studies on two populations of feral pigeons in highly urbanized areas. We predicted that darker coloured individuals would exhibit higher survival and/or philopatry (integrated into ' local survival ' ) than paler coloured ones. No diff erence in local survival was found between adults of diff erent colouration intensities. However, on one site, we found that darker juveniles had a higher local survival probability than light ones. Juvenile local survival on that site was also negatively correlated with the number of chicks born. Th is suggests the existence of colourand/or density-dependent selection processes acting on juvenile feral pigeons in urban environments, acting through diff erential mortality and/or dispersal.

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Se comunica la presencia de 153 especies de briófitas y antocerotófitas en la lsla de Cocos ·(5032'N, 870Q4'W). Costa Rica. Estas son 98 especies de hepáticas en 43 géne ros y 10 familias; 54 especies de musgos en 33 géneros y 17 familias Y una especie de antocerotófita. Más del 60% de las briófitas tiene amplia distribución en el Neotrópico, 10.4% distribución pantropical, 9.7% pertenecen al ele. mtlnto Caribe, 1 .3% al elemento Centroamericano, 4.5% al Nor-sudamericano, 3.2% son endémicos, 1.3% 'subendémicos y 1.3% subcosmopolitas.